The Establishment Of Passenger’s Vibration Model On High-Speed Train And The Analysis Of Vibration Response

With the rapid development of high speed train, traffic safety is effectively guaranteed Passengers’demand on comfort is increasingly high. Nowadays the passengers’comfort is measured by the high speed train’s running smoothly in China. Although the vibration of train is the main resource of discomfort, the evaluation of human comfort should take human as the research object rather than the train. The impact of the high speed train on human be-ings is still unclear. In this paper we developed the human-train coupled vibration model, at the meantime we used the track irregularity signal as the input of the model to research the vibration response of human tissues and organs. It mainly included the following aspects:(1) Simplify the human body as a mass-spring-damping mechanical system with lumped parameters, we respectively developed human vertical and horizontal vibration model. Considering that there was coupled effect between human and train via the connec-tion of the seat and other objects, we separately established human-train vertical and hori-zontal coupled vibration equations. At the same time we developed the vibration simulation model with SIMULINK, We used the cubic spline interpolation method to expand the human vibration test data. Based on the principle of least squares, we used the MATLAB optimiza-tion toolbox as tools to identify the parameters of human vibration model.(2) We regard the track irregularities generated by German low interference power spec-tral signal as the input and loaded it on the coupled vibration models to research the response of human head and viscera. The results showed that if the train was undergoing the vertical vibration, when the vibration frequency ranged from 1 to 2 Hz, the amplitude of head and viscera is roughly equal with the train; When the frequency reached to 4-6Hz, the vibration of the viscera was much stronger than the vibration of human’s head; When the frequency was between 10 and 12Hz, the vibration magnitude of human’s head was higher than hu-man’s viscera. If the train was undergoing the horizontal vibration, when the vibration fre-quency ranged from 1 to 2 Hz, the vibration of the viscera was much stronger than the vibra-tion of human’s head; When the frequency was between 2and 5 Hz, the vibration magnitude of human’s head was higher than human’s viscera.(3) To reduce the calculation amount of Sperling value in different speed, we limited the speed between 150 to 350 km/h and calculated the vertical and horizontal Sperling value of human organs and the train. Compared the results, we can concluded that the stability index of both human and the train rose with the improvement of the speed. We could also see that the stability index of viscera was bigger than the head. Both of them were higher than the stability index of the train. It showed that it was not responsible to use the stability index of the train to evaluate human comfort. It would overestimate the real feelings of passengers.(4) In order to research the influence of different track irregularity signals to the re-sponse of human vibration, we used the single loading method to test and analyzed the re-sponse. The results showed that the vertical track irregularity was the main factor affecting the response of human vertical vibration. The effect of horizontal track irregularity was small. Both of orbital direction irregularity and creamy level irregularity were the main factors on the horizontal vibration of human beings. In this paper, we also used the white noise as the input to load on the coupled models. Through mapping the power spectral density curve of human vertical and horizontal vibration, we researched the energy distribution of human loading vertical and horizontal vibration with different frequency.Through the research of vertical and horizontal response to human body, we concluded that it was not reasonable using the stability index of the train to estimate the feelings of passengers. We got the resonance frequency range of different part of the body and the in-fluence of different track irregularity signals to human comfort. It provided the technical ref-erence for the improvement of passenger comfort in the construction of the track and the de-sign of the new high speed trains.